Which operations are expecting input in radians and which in degrees?
You can input a value in either radians or degrees by appending a "d" suffix (for a value in degrees) and a "r" suffix (for a value in radians) to the numerical value.

"1.5913513r" => in radians

"1.5913513d" => in degrees

For example, if you click the X-axis rotation button of an object to input a rotation value manually, and write "1r", after you press ENTER to commit the value the button will show 57.3º. Hovering the mouse over the button will show a tooltip saying "radians: 1.000000" (and 57.3 degrees is the approximate value of 1 radian).

You can use this when editing drivers, rotations etc. in case you prefer one unit over the other, and Blender will do the conversion for you.